天博体育 in the press | Key factors influencing clay calcination
天博体育 features in the March issue of World Cement magazine, discussing key factors in clay calcination processes and presenting its latest insights following further testing carried out at its research and testing centre.
Our paper explores the critical parameters of calcination after comparing two calcination technologies: the flash calciner and the rotary kiln, highlighting their respective performances.
Clay suitability assessment
Analysis of the clay's mineralogy and chemistry is essential to determine its suitability for calcination. Pilot-scale tests are required to confirm its properties and ensure optimal performance.
After the flash calcination process, clay becomes a supplementary reactive cementitious material (SCM), essential in the decarbonization strategies of the cement and construction industries.
Calcination technologies:
- Flash Calciner: offers the best overall performance and versatility thanks to its four independent process stages (heat generation, calcination, color control, final cooling). It can operate up to 1300°C, making it suitable for other types of materials.
- Rotary Kiln: A 4-metre rotary kiln providing a residence time of 30 minutes, suitable for the production of calcined clay and clinker.
Key calcination parameters:
- Temperature: insufficient heat reduces reactivity, while excessive heat induces sintering and crystallisation reactions.
- Particle size distribution: an appropriate grinding sequence is crucial to the efficiency of the process.
- Residence time: varies between technologies, influencing the uniformity of calcination.
Conclusion
The optimization of clay calcination relies on a balance between temperature, particle size distribution and residence time. Tests confirm the superiority of the Flash calcination technology, which stands out for its precise control and superior reactivity, supported by 天博体育 FCB expertise.